When JD and Petey first meet, Petey shakes JD's hand twice.
When JD and Perry are talking about the latter's "jealousy", Laverne (in the background) is alternately facing the front door or facing the fax machine between cuts.
Turk cuts the plug off of the power cord for the Ms. Pac Man machine in the doctors' lounge, in retaliation for Dr. Kelso parking his car in the middle of the younger doctors' basketball court. But later, when Perry and Peter are having their confrontation in the lounge, the marquee of the Ms. Pac Man is lit.
At the beginning of the fight scene between Dr. Cox and Dr. Fisher, the clock on the wall shows 11:34. Right after the fight, it's 11:32.